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Happy People Work Harder, And Giving Them Chocolate Helps, Too

Whether you’re a powerful CEO or a humble line manager, and you want to make your employees work a little bit harder, try making them happy. Or at least slip them some chocolate, says a recent study.

Economists from the University of Warwick have found that giving people chocolate and showing them videos of stand-up comedy increased productivity by 12 percent. The randomized study is the first, they argue, to find a causal link between increasing people’s happiness and boosting worker productivity. And while the research may have trouble drawing any conclusions for creative work, it opens doors for the general mechanisms behind employee satisfaction.

To understand how happiness-based incentives may trigger productivity, the research team recruited over 700 participants to perform various math problems. One group was given a piece of chocolate or fruit, or asked to watch a set of comedy DVDs prior to the tasks. Meanwhile, the other watched a placebo video and received no food.

The task involved correctly adding up series of five two-digit numbers. Subjects had 10 minutes to complete it. Prior to the experiment, each subject completed a baseline test for their standard productivity in that time. Overall, the group given chocolate or fruit or comedy videos performed better than the control group, by an average of two more questions answered correctly.

Follow-up tests showed the reverse effect as well. When subjects were asked to recall a recent tragedy in their lives, productivity decreased. By the researchers’ own admission, this finding isn’t exactly new. Business managers have known for decades that keeping workers engaged and satisfied is the key to making them most productive. But the key point, they argue, is in the details.

“These experiments have the advantage that we can directly control the happiness shock,” the researchers explained in their report. Of course, with any clinical experiment that seeks to mimic the real world, there are downsides, too. Here it’s that the “shocks are inevitably small and of a special kind in the laboratory.”

In other words, while it’s unlikely any manager is going to distribute chocolates to his or her employees throughout the day, the principle behind the gesture holds true. Unhappy workers produce work of a lesser quality, and happier workers do better — whether it’s because of their managers or not. “The key lesson for managers from our research,” said researcher Eugenio Proto, according to The Conversation, “is that more happiness will not result in more distraction.”

Of course, you could always bring your own chocolate and stay happy the entire day. Until the stomach ache kicks in, at least.